In an x-ray CT (computed tomography) apparatus used in medical sites and the like, x rays passing through a photographic object are received by scintillators, and photodetectors detect light emitted therefrom. In addition, these detectors are disposed to form a two-dimensional array, and the scintillators are separated from each other by partitions so as not to cause crosstalk of light.
Since having no contribution to the x-ray detection and degrading a spatial resolution, the partitions are each preferably formed as thin as possible. For example, in PTL 1, a technique has been disclosed in which after many scintillator crystals are bonded to each other with an adhesive to form a scintillator array, the adhesive is removed by etching, and spaces formed thereby are filled with a titanium oxide powder functioning as a partition material. In this case, according to the above patent literature, the thickness of the partition can be decreased to approximately 1 μm.
Since a related scintillator has no function to guide light therethrough, partitions functioning as a scattering surface and/or a reflection surface are required. However, by the technique disclosed in PTL 1, although the thickness of the partition can be decreased, the partition itself cannot be eliminated. In addition, in a manufacturing process, many steps, for example, from cutting of a scintillator to bonding for partition formation are required.